Recent discoveries in geospace science have necessitated the design of compact UV imaging instruments to make space-based observations from multiple vantage points. The miniaturized ultraviolet imager (MUVI) instrument from the Space Sciences Laboratory (SSL) at UC Berkeley is under development to facilitate such discoveries on a wider scale. This thesis documents the design, integration, and characterization of a vacuum compatible manipulator to calibrate the MUVI instrument inside the UV thermal vacuum chamber at SSL. Precision linear and rotation stages were implemented with custom mounting plates to achieve four degrees of freedom. Optical components were installed to imitate the MUVI instrument for testing purposes. A customized PCB was fabricated to control the stages and receive position feedback data. A Graphical User Interface was programmed and utilized to position the manipulator during experimental validation. Field of View sweeps were conducted using visible light and a monochromatic CMOS sensor to track the coordinates of a laser's centroid. An analytical model of the optics assembly was developed and later refined from the experimental results. Using this model, the translation stages successfully compensated for optical misalignments. Analysis of the performance data showed the pointing resolution of the manipulator was less than 1 arcmin, which satisfied the calibration requirement for the MUVI imager.

This thesis describes the design, assembly, and test of the FTDS-K, a new device in the Boundary Layer Data System (BLDS) family of flight data acquisition systems. The FTDS-K provides high-frequency, high-gain data acquisition capability for up to two pressure sensors and an additional three low-frequency pressure sensors. Development of the FTDS-K was separated into a core module, specialized analog subsystem, and practical testing of the FTDS-K in a flow measurement mission. The core module combines an nRF52840-based microcontroller module, switching regulator, microSD card, real-time clock, temperature sensor, and trio of pressure sensors to provide the same capabilities as previous-generation BLDS-P devices. An expansion header is included in the core module to allow additional functionality to be added via daughter boards. An analog signal chain comprised of two-stage amplification and fourth-order active antialiasing filters was implemented as a daughter board to provide an AC-coupled end-to-end gain of 7,500 and a DC-coupled end-to-end gain of 50. This arrangement was tested in a wind tunnel to demonstrate that sensors with a full-scale range of 103 kPa can be used to reliably discriminate between laminar and turbulent flows based on pressure fluctuation differences on the order of tens of Pa. A combination of wind-off correction and band-filtering was used to reduce the effect of inherent and induced electrical noise, while two-sensor correlation was tested and shown to be effective at removing certain types of noise. Total power consumption for the FTDS-K in a representative mission is 208 mW, which translates to an operational endurance of 9 hours with 2 AAA LiFeS2 cells at -40°C.

This report describes the design, building, and testing of the Structure Climbing Monkey Robot (SCMR). It is composed of seven successive joints and linkages with two grippers at the two ends. Each gripper can act as the base or the end of the robot. The SCMR has the ability to climb any structure. The gripper plates can be changed to grab different kinds of structures, but this one is made to grab 2x4‘s. A program was written to assist the user to grab four non-coplanar, non-orthogonal points. The SCMR is actuated by a total of nine motors: two to open and close the two grippers and seven to control the movement of the SCMR. Planetary gear motors are used with a worm gear to control the motion of each joint. The worm gear increases the torque of the motor and reduces the rotational speed to a usable value. The SCMR is just over 45 inches long and weighs about 30 pounds. The motion of the SCMR is controlled by the microcontroller Arduino Mega 2560, Vex Robotic quadrature encoders, and Pololu 18v15 motor driver chips. Code was written in the languages Arduino and Processing to actuate the motors and create the GUI, respectively. The motors can be controlled individually or run simultaneously while incrementing a specified angle.

This thesis will focus on creating electromagnetic vibration generator for a project ESPOSA. This generator will be used in aeronautical application. There it will be powering required electronics. Electronics is thought a part, which will be sensing, writing and sending required data.

Le couplage d’un traitement électrochimique avec un procédé biologique est une alternative prometteuse pour la dégradation de composés organo-halogénés biorécalcitrants dans l’environnement. Les procédés d’électroréduction, connus pour couper sélectivement la liaison carbone-halogène, ont été mis en oeuvre afin de réduire la toxicité des molécules cibles et augmenter leur biodégradabilité avant une minéralisation totale des polluants par un traitement biologique. Pour améliorer le rendement de déchloration, la cathode préalablement nickelée a été modifiée par des nanoparticules d’argent car l’argent est considéré comme l’un des meilleurs catalyseurs pour couper sélectivement la liaison carbonehalogène. Le feutre de graphite a été choisi comme support d’électrode pour sa grande surface spécifique. Le principal produit de déchloration de l’alachlor s’est révélé être biorécalcitrant. Pour surmonter ce problème, un traitement par procédé électro-Fenton a été mis en oeuvre pour dégrader les polluants cibles. Une amélioration significative de la biodégradabilité de la solution d’alachlor a pu être observée après le traitement électro- Fenton, et qui est renforcée quand l’atome de chlore a été préalablement éliminé de la structure de l’alachlor par électroréduction. Le bismuth a été également utilisé comme support d’électrode du fait de sa grande surtension visà- vis de la réduction de l’eau. Une grande sélectivité a pu être obtenue sur cathode de bismuth lors de la réduction d’herbicides du type chloracétamide. La réduction électrochimique du dioxyde de carbone a également été réalisée sur électrode de bismuth modifiée par des nanoparticules d’argent comme autre application de cette nouvelle électrode. / Electrochemical process coupling with a biological treatment is a promising alternative for the degradation of biorecalcitrant organo-halogenated compounds in the environment. The electroreduction treatment, known to cut selectively carbon-halogen bonds, was first implemented to decrease the toxicity of the target molecules and increase their biodegradability before a complete mineralization of the pollutants by a biological treatment. To improve the dechlorination efficiency, the cathode was modified by silver nanoparticles after a previous nickelisation, since silver is considered as one of the best electrocatalysts to selectively cleave the carbonhalogen bond. The graphite felt was chosen as the electrode support due to its high specific surface area. For alachlor herbicide, deschloroalachlor, the main by-product after dechlorination, was still biorecalcitrant. To overcome this issue, electro-Fenton treatment, in which hydroxyl radicals were generated to degrade the target pollutants, was implemented. Significant improvement of biodegradability of the alachlor solution was observed after electro-Fenton treatment, which was further improved when the chlorine atom was beforehand removed from the alachlor structure by the electroreduction process. Bismuth was also used as electrode support due to its high overpotential for hydrogen evolution. A high selectivity of chloroacetamide herbicides reduction was observed on the bismuth based cathode. As an extended application of the bismuth based cathode, the electrochemical reduction of carbon dioxide was performed on Bi electrode modified by silver nanoparticles.

This thesis discussed the mobile land robots for the robotic competitions. The topics discussed in this thesis are robotic systems, mobile land robots, robot competitions, and example of robot designs. Question-answer sections are added to help understand the requirements to build the robot. Examples include three different teams who participated in different robotic competitions to provide a context for robotic competitions. The thesis was divided into the five chapters. The first and second chapters explained the different kind of robotics systems, and opportunities. The focus of the information was the mobile land robots, which was explained under the third chapter, mobile land robots. The aim of the thesis was to guide those who want to design, build, and compete in the mobile robot competition. As a result, the information from various resources been gathered and has been given a form of thesis to help individuals or group of individuals to guide them through the robotic competitions.

Microwave photonic applications in the terahertz (THz) region of the spectrum are attracting increasing attention due to the need to find solutions for next-generation (5G/6G) wireless communication systems capable of handling unprecedented data rates. It is crucial to develop millimeter-wave (mm-wave) (30-300GHz) fiber supported transport networks. One of the key questions is, which carrier frequency generation technique will be the most suitable for THz signals above 300 GHz; electronics-based or photonics-based. Since the backbone of the wireless networks is composed by very high-capacity fibre optic cables, the microwave photonic approach has the ultimate advantage of seamless integration with existing optical fibre networks. Although the cost effectiveness is still an open question, simplistic base station architecture with simplified antenna units and high optical component reuse is necessary for enabling a compatible mobile network backhaul. For THz applications a broadband electro-optic modulator (EOM) with a frequency response extending to the sub-terahertz range, high power handling, and very low nonlinear distortions, is required. The objective of this thesis is to study the feasibility of photonic integration and, proof of concept implementations with the effective use of optical components with reduced energy consumption, reduced footprint and offer speed beyond all-electronic implementations. The first study presents a coherent electro-optic photonic integrated circuit deploying generalized Mach-Zehnder interferometer (GMZI) substituting N×1 combiner by an optical N×N discrete Fourier transform (DFT) in order to generate a regularly spaced frequency comb. The proposed design comprises of 1×N splitter that feeds light into a parallel array of N electro-optic phase modulators electrically driven by RF signal with a progressive phase shift with their phase modulated optical outputs processed by an N×N optical DFT. A pragmatic design approach and analytical formulation for implementing MMI based optical DFT in photonic networks composed of waveguide splitters, combiners, and phase-shift elements with necessary circuit diagram for even and odd dimensions are presented. Recently, there has been impressive progress toward ultra-wide band low voltage EOM. The heterogeneous approach of utilizing silicon nitride on lithium niobate waveguide integrated on a single chip is demonstrated for the best optical modulation performance that opens a wide range of opportunities for universal linear optical networks, chip-scale MWP systems, ultra-speed switching of optical communications. Finally, the third study de-scribes the architecture for compact on-chip spectrometry targeting high resolution across the entire C-band to measure the spectral profile of WDM signals reliably and accurately in fixed and flex-grid architectures. The design architecture of technologically viable com-pact on-chip high-resolution wideband spectrometer such as Mach-Zehnder delay interferometers (MZDI), 2×2 directional couplers and multimode interference couplers is presented and verified by software simulation using an industry standard tool. The components simulations that supported the assessment of the feasibility of a spectrometer compliant with the specification made use of the LioniX asymmetric double strip (ADS) waveguide and the low-cost photolithography.

>Magister Scientiae - MSc / Anode catalysts are one of the key components of direct alcohol fuel cells (DAFCs). They play a huge role in the alcohol oxidation reaction (AOR) that occurs on the anode side. Palladium (Pd) supported on carbon material has been reported to have good catalytic activity towards alcohol oxidation reactions. Better stability and activity has been reported for catalysts supported on conductive polymers like polypyrrole (PPy) when compared to traditional carbon support material. This study investigated the effect of support materials on Pd and PdCo electro-catalysts while concurrently determining the support material that can improve the activity and stability of Pd and PdCo electro-catalysts used as direct alcohol fuel cells catalysts. All Pd and PdCo catalysts supported onPPy (prepared using oxidative polymerization method), reduced graphene oxide (rGO) and prepared using modified Hammers method and multi-walled carbon nanotubes and pre-treated by acid. All the catalysts were synthesized using the modified polyol method.

The biodiesel industry produces millions of kilograms of low-value glycerol, which must be either stored or disposed of, creating environmental concerns. Even though glycerol is utilized as a raw material within various industries its supply is still superior to the demand. Upgrading this biodiesel by-product into value-added products using electrochemical technologies is a promising approach and will make biodiesel production more environmentally friendly with added financial benefits. Precious metals are the state-of-the-art electro-catalysts for the oxidation of organic compounds, and so are a logical choice for the electro-oxidation of glycerol. Two factors that hinder their use in this regard for commercial applications include their cost and susceptibility to poisoning by the carbonyl (CO) species formed during the electro-oxidation process. The use of inexpensive transition metals as the principal metals in a catalyst composite is thus appealing, leading to the selection of nickel (Ni). Furthermore, its high activity, anti-poison ability and long-term stability in alkaline solutions make it an attractive candidate for glycerol electrooxidation reaction (GEOR). The main thrust of this work is to develop a deeper understanding of the factors involved in controlling the selectivity of the product reaction without 3 carbon cleavage on non-precious metal surfaces. To overcome a trial-and-error approach, we took advantage of modern synthesis and characterization techniques for metal alloy nanoparticles and advances in rapid identifications and quantifications of products based on infrared spectroscopy. These tools were expected to provide the foundation for the detailed understanding of GEOR mechanism hence would pave the way for the rational design of catalysts to produce specific high value-added chemicals. We cared out extensive research to determine the effect of size, morphology, shape, support, experimental conditions and catalyst preparation methods on the catalytic performance of Ni. The thesis aims to demonstrate how the selectivity of unsupported Ni nanoparticles for GEOR can be improved via interaction of Ni with low noble and transition metals content. Enhanced selectivity towards C3 and C2 products such as glycerate, lactate, oxalate and tartronate, was achieved by simply adding less than 20 atomic percent of any of bismuth (Bi), Pd or Au onto Ni nanoparticles. Furthermore, the composition effect of carbon supported NiₓM₁₋ₓ (M = Bi, Pd and Au) nanomaterials were combined with Pt/C and commercial silver nanoparticles for cathodic hydrogen production and CO₂ electro-reduction, respectively. These rich-phase of Ni(OH)₂ catalysts were highly active and selective towards C-C bond breaking products leading to 100% selectivity of formate after 1 hr electrolysis and 100% conversion of glycerol after 24 hr at +1.55 V. Lastly, the first principles calculations based on the density functional theory (DFT) insights provided an explanation to understand the electronic structure, magnetism and reactivity of our catalysts. Core@shell (Mm@Nin) nanoparticles of 13-, 54- and 55-atoms with different elements concentrations matched the experimental results and assisted us with a better understanding of some of the microscopic phenomena involved with the reactivity of bimetallic nanoparticles.

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